This is a charade - two separate words or phrases are joined together to form the answer.
Split this into two parts: 'Relaxed' gives you the first word, and 'government unit' gives you the second word. Put them together to get something that will indeed keep things fresh.
Answer: CHILL CABINET | This is a charade of CHILL (relaxed, as in 'chill out') + CABINET (government unit). A chill cabinet is a refrigerated storage unit that keeps things fresh.